This research concentrates on the consequences of environmental shifts on physiology and behavior. Integrating across various biological disciplines, visual sensory physiology, behavior, molecular genetics, and multivariate statistics. The goal is to resolve the relationship between visual sensory physiology, visual signal design, and the environment. This research will produce new insight into how environmental variation such as spectral quality and structural composition affects behavioral and physiological phenotypes within and between populations of the same species. In particular, results from this research will provide key insights into the plasticity of vertebrate visual systems. The focal study species approach the minimum size of any amniote vertebrate; thus, they make an excellent prospect for future biomedical research, especially regarding the physiological constraints accompanying small body sizes in vision and neural science and the allometry of eye size. An important and growing area of research in biomedical sciences is to translate from genomic sequences through physiological outcomes to behavioral changes. This research provides a method for integrating information and material across these different levels in biology. [unreadable] [unreadable] [unreadable]